"tokenUrl": "token",
            "scopes": {"read:users": "Read the users", "write:users": "Create users"},
        }
    }
)


class User(BaseModel):
    username: str


# Here we use string annotations to test them
def get_current_user(oauth_header: "str" = Security(reusable_oauth2)):
    user = User(username=oauth_header)
    return user


@app.post("/login")

    return user


@app.get("/users/me")
async def read_users_me(current_user: Annotated[User, Depends(get_current_user)]):

    return user


@app.get("/users/me")
async def read_users_me(current_user: Annotated[User, Depends(get_current_user)]):

app = FastAPI()

security = HTTPDigest()


@app.get("/users/me")
def read_current_user(credentials: HTTPAuthorizationCredentials = Security(security)):
    return {"scheme": credentials.scheme, "credentials": credentials.credentials}


client = TestClient(app)


def test_security_http_digest():
    response = client.get("/users/me", headers={"Authorization": "Digest foobar"})

client = TestClient(app)


def test_security_http_bearer():
    response = client.get("/users/me", headers={"Authorization": "Bearer foobar"})
    assert response.status_code == 200, response.text
    assert response.json() == {"scheme": "Bearer", "credentials": "foobar"}


def test_security_http_bearer_no_credentials():
    response = client.get("/users/me")
    assert response.status_code == 200, response.text

async def get_items():
    return [
        {"name": "Plumbus", "price": 3},
        {"name": "Portal Gun", "price": 9001},
    ]


@app.post("/users/", response_model=ResponseMessage, tags=["users"])
async def create_user(user: User):

client = TestClient(app)


def test_create_user():
    response = client.post(
        "/users/",
        json={"email": "******@****.***", "password": "chimichangas4life"},
    )
    assert response.status_code == 200, response.text
    data = response.json()
    assert data["email"] == "******@****.***"
    assert "id" in data
    user_id = data["id"]

    response = client.get(f"/users/{user_id}")

* `/items/public/`
* `/items/private/`
* `/users/{user_id}/activate`
* `/items/pro/`

⤴️ 👆 💪 🚮 🎏 ✔ 📄 🔠 👫 ⏮️ 🔗 & 🎧-🔗:

```mermaid
graph TB

current_user(["current_user"])
active_user(["active_user"])
admin_user(["admin_user"])
paying_user(["paying_user"])

public["/items/public/"]
private["/items/private/"]
activate_user["/users/{user_id}/activate"]
pro_items["/items/pro/"]

activate_user["/users/{user_id}/activate"]
pro_items["/items/pro/"]

current_user --> active_user
active_user --> admin_user
active_user --> paying_user

current_user --> public
active_user --> private
admin_user --> activate_user
paying_user --> pro_items
```

## Integrated with **OpenAPI**

All these dependencies, while declaring their requirements, also add parameters, validations, etc. to your *path operations*.

再次查看这个依赖项树与作用域。

`get_current_active_user` 依赖项包含子依赖项 `get_current_user`，并在 `get_current_active_user`中声明了作用域 `"me"` 包含所需作用域列表 ，在 `security_scopes.scopes` 中传递给 `get_current_user`。

*路径操作*自身也声明了作用域，`"items"`，这也是 `security_scopes.scopes` 列表传递给 `get_current_user` 的。

依赖项与作用域的层级架构如下：

* *路径操作* `read_own_items` 包含：
    * 依赖项所需的作用域 `["items"]`：
    * `get_current_active_user`:
        *  依赖项函数 `get_current_active_user` 包含：